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Overhead Construction
Published in Anthony J. Pansini, Guide to Electrical Power Distribution Systems, 2020
This wire has a tough, outer covering which can withstand considerable abrasion. Figure 5-5 shows a plastic-covered wire which is often used for this purpose. This wire provides partial insulation as well as a tough covering for wires operating at higher voltage values. There are also other types of tree wire.
Servo Valves
Published in John S. Cundiff, Michael F. Kocher, Fluid Power Circuits and Controls, 2019
John S. Cundiff, Michael F. Kocher
A tachometer (several different designs available) is widely used as the feedback transducer for a rotary velocity servo. This type of transducer can be expected to have a long service life if the tachometer shaft is connected to the load using a flexible coupling to avoid bearing wear due to misalignment. Because the output signal is dc, the output cable must be shielded to avoid signal errors from ambient electromagnetic noise. A shielded cable has a metal foil inside the insulation that encloses the signal wires. This metal foil is grounded, and it tends to absorb interference that would otherwise be superimposed on the signal.
Solar Energy
Published in Sergio C. Capareda, Introduction to Renewable Energy Conversions, 2019
The wire size is calculated using Equation 2.20. The wire size (Aw) is usually reported in units of mm, while WL is the load in watts, V is the system voltage, and L is the length of wire in meters. The standard wire gauge in the United States is called the American wire gauge (AWG), also known as the Brown and Sharpe wire gauge. The dimensions of the wires are given in ASTM Standard B 258. The cross-sectional area of each gauge is important for determining current carrying capacity. Increasing gauge numbers mean decreasing wire diameters. For example, AWG#16 has a diameter of 1.291 mm [0.0508 in], AWG#14 has a diameter of 1.628 mm [0.0641 in], AWG#12 has a diameter of 2.053 mm [0.0808 in], and AWG#10 has a diameter of 2.588 mm [0.1019 in]: Awmm=0.04×WLV×L
Modeling and simulation of a compact push–pull rubber actuator energized by an outer coil of shape memory wire
Published in Mechanics Based Design of Structures and Machines, 2018
Eugenio Dragoni, Giovanni Scirè Mammano
Figure 7 displays the lateral view and the 3D rendering of a prospective prototype actuator based on the title concept. Two end plates with threaded plugs for load attachment are bonded or cocured to the faces of the solid rubber core. A single layer of SMA wire is closely wound between the shallow rims of the core and is attached to electric terminals placed on each end plate. By folding the SMA wire over itself before winding would allow the terminals of the actuator to be placed on the same end plate, which would be more convenient both mechanically and electrically. Electrical insulation of the wire to avoid short-circuiting during supply can be provided by dielectric coating (Boccaccini et al., 2006). Another improvement that can be brought into the concept is the use of multiple layers of wound wires. This would proportionally increase the useful force for given stroke. A prototype actuator based on the sketch in Fig. 7 is now under construction for thorough experimental characterization.